Apparatus for increasing the temperature of combustion in gas-fired furnaces.



H. L. DOHERTY. APPARATUS FOR INCREASING THE TEMPERATURE OF COMBUSTION IN GAS FIRED FURNACES. APPLICATION FILED APRA, 1912.

L1 33317290 Patented H0117, 1914.

a SHEETS-SHEET 1.

H, L; DOHE RTY. I APPARATUS FOR INCREASING THE TEMPERATURE OF COMBUSTION IN GAS. FIRED FURNACES.

APPLICATION FILED APR. 1912.

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3 SHEETSSEEET 2.

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H.L.DOHBRTY. APPARATUS FOR INCREASING THE TEMPERATURE OF COMBUSTION IN GAS FIRED FURNACES.

APPLICATION FILED APR. 4, 1912. I

1, fi fm Patented N0v.17,1914-.

3 SHEET$-SHEET 3.

macaw? I axwawtz e r Until nil) banal are APPARATUS FOR INCREASING THE Original application filed March 31, 1909, Serial No. 486,888.

Patented New 37, 1914:.

1912. Serial No. 688,539.

To aZZ whom it may concern Be it known that I, HENRY L. Donnnrr, a citizen of the United States, and a resi dent of New York city, in the county of New York and State of New vYork, have invented certain new and useful improvements in Apparatus for Increasing the Temperature of Combustion in Gas-Fired Furnaces, of which the following is a specification.

My invention relates to apparatus for increasing the temperature of combustion in gas-fired furnaces; and it relates particularly, to that type of such apparatus 111 which the gas producer and gas-tired furnace are functionally connected and wherein the control and regulation of the temperature in the producer is secured by the introduction of some endothermic agent.

The objects of my invention are, the increase in efiiciency of heat utilization due to the increased temperature secured in the furnace, and thetincreasedeconomy in fuel due to a more perfect recuperation of the heat of the flue gases, than is secured by the various apparatus in present use.

My invci 'ion can be applied to any gasproducing-and-consuming apparatus, in which the waste. gases of combustion are at a higher temperature than the producer gas leaving the gas producer. i

My invention can be used equally Well in connection with either the type of producer wherein the temperature control water vapor or wherein the temperature control is cilected by the introduction of a regulated proportion of combustion gases into the air current supplied to the producer.

This application is a division of my ap plication Ser. .LTO. 286888, filed Mar 31st, 1909, in which I claim the process involved.

The particular application oi my invention which I have selected for purposes of illustration. that of a furnace for mamrf The name commonly applied to this apparatus is gas bench. These are usually built back to back, forming twin settings, a number oi these being erected side by" side, forming what is known as a battery? or stack of benches. My invention, how" ever, is not limited in its application't this particular type of apparatus. It may" temperature than that at which the pro ducer gas enters it, the relation of the two parts of the apparatus being such, that the" Divided and this application filed Ap TEMPERATURE OF CUIvIBUSTIQN IN GAfi-FIREZ) FURNACES.

Specification of Letters Patent.

products of combustion may be passed into recuperators for heating the producer gas at, substantially, the temperature at which they leave the furnace. For instance, my" invention maybe applied to zinc furnacesor open-hearth steel furnaces, and to many other similar types of furnaces. I 111 the accompanying drawings, 1 show bench to illustrate the application of my more or less diagrammatically a single gas" invention to such apparatus. The bench.

shown in Figures 1-, 2 and 3, is of a common type that is, at present, used in the art with the addition of my invention. In this type,

.the temperature regulation of the gas producer is accomplished by the use of waste' gases containing reducible amounts of carhon dicxid.

My invention can be applied equally well the temperature control of the produceris thereof is eil'ected by the introduction ot eiiected by the introduction of water or water vapor into the fuel bed, in e and 5 1 illustrate an application to such type of apparatus adapted to preheat the primary draft current.

y In the drawings, Fig. 1 shows a single bench partly in section and partly in eieQ vation. llig. Z is a longitudinal section on the line A E of 1. Fig. 3 is a sec tion through a recuperator on the line U--D of Fig. 1. a is part cross-section of a bench of the type in which. the control of the temperature of the fuel bed is se cured by the use of flue gas, and the pri; mary draft current is preheated. 5 is partial half, section of the type of bench in which water vapor is used to control. the temperature of the fuel lied, and the water is evaporated by the heat the hot comhustion gases.

- in ec- Ty 1 an 51 are ncxiw *he 'pri um 11s the -pu iues 7 ed m" The $071 ators i you asses into i313 Hm-"h the 110551? and s11 my pi we martian of structmn 511116111511 Enemy 1 a mine ed. inw

grate g propemtors e producer gas tin the 1? the recnpamunder ores conveyin roduc 1 is th pro air tor; flue as l'ecu conduc 011 the. Sid-e,

051mm. 3., 1 is 05; means of mic? we 3* is i ugh Which the injec 5 are p1 ducer w" Hues; 8 th racuperator for 30. he Pa-Wi :21 The Zil the 1 Q2: 0 i; (i

12 pa 1% pplied to c o Lui in @1101 S 11mm 121 the is the i ture of Bi" produce 3 is a pi sure is s the xodu (Inger gas 4 are em (a through 9 and 1 0 producer ga to waste conibumy etmi; we and 9 he eqz who me for 1 rate ator ed, eris ach aste ga 1w :1 s to to far e bani the w am the r (one h providi mg flue port 23 pemtor 11 be c Whic to re ulate "5 air from of the flu are ire, more r the with result uld form large aggregaoed. known as clinkers. -l, in time, almost conint the passage of the gaseous the producer. By the second U011. however. which I make use of 111 irer, this r reuction, every'pound 1c fuel so consumed, about absorbed and rendered LPiit that by properly oiooortion of combustion nut maintain any desired producer. gas A from the fuel c p oducer is taken oil from the l 1 the tines 5 and passes 1c equalizing lines '7 of the These tlues '7 are simply me length of the reg to distribute the uni iorr; i throughout the -ie recline-rotors. These pro have vertical pertito support the fines do the main producer- The prou h the fines 8, passes orizontzii fines 14, receiving from the same and having its temperaincreased.

producer leaves the re- ;neiigh the tines 9, the currents orresgondingilues, 9, on either hench joining and passing 10, into the combustion oven. Here the prosecondury air and burns. v :iir cote the recuperators, inlet tines l8, thence series of return-bend through the re contrary to the through the 1, l5, and 14. The of metal of relatively while the upper lues, 4-, l as fire clay, possessing wtoriness.

-he use of ii h conductivity for .ae recuperator enables iii-ally as high a temperay air as 1 could secure of reeuperator such as I tent 829105, dated Aug. referred to, although in tion I am entering the flue secondary air recnperator at i inperatiire.

ted secondary air leaves i3 1, lii ,'tln"ough the port,

' seen 31, and passes into the equalizing fine, 22.

song this due, as shown. are small orifices or ports, 23, having niorahlc tiles, 25, which may be adjusted by means of a metal rod or hoe worl-zed through a siiitable lizindhole at the end of the flue, so as to regulate the free area of the ports, 23. By this means I am able to secure a practically uniform flow of the secondary air into the line, 24:, along its whole length. From 2 1 the secondary air passes upwa rd through the tines, 26, into a flue, 527. From 27 the air is distributed to the nostrils, 28, from which it discharges into the combustion chamber of the retort oven, burning the producer as entering through 10. T 1e products of this combustion pass up and around. the retorts, imparting tOtllC latter part of their sensible heat, thence to the upper fines, 13, of the recuperators from which, part of the gases pass through the tines M and 15 to the stack and part to the injector. The part going to the injector is passed into the fuel bed in the manner already explained. The main current of combustion gnses passes from the discharge fines of the recuperetors through the lines, 16, to the stack, whence the gases discharge into the atmosphere.

in the operation of a bench such as is shown in my co-pending application Ser. No. 421562 filed May 23rd, 19.1.1, with my present invention applied thereto (see Fig. l), the principal difference from the method of operation described above is that the primarr air is led through a recupcrutor, for preheating by the sensible heat of the comhustion gases, before discharging into the injector. in this type of bench, as shown, the primary air recuperator is located in one side of the producer and the secondary air recupcrator on the other side. The second ary air recugerator is very similar to the one lierciuhetorc described, except that 'passages, 3; nostrils, on hench with in the recuperator, e5. cupcrator, e1, consists bend fines, 43, lisvirg small r fines, e2, located Within them. 'liicup ierinost fine, 13, receives the current of flue gas that has passed through lef -hand producerges recuperator, 6, the gas passing throu h the fines, 4.3, in series, and discharging into a flue leading to the stack. The fines, 42, are simply metal 1 ntering headers in the front and back recuperator, the ad jacent sectio' sof the headers being,'a-ltc1- nately, SGQZH'tLlIQCl and in communication so as to term a return-bend flue. The heated primary air .ischerges from the; recuperator, 41, through the nozzle of the inductor, 4.5. The action of the inductor (lows in a portion of the waste combustion gases through the fines, 4G, and

the leftliand side of the Tiheprinisry air re- 01 a series 0t returnhalf the secondary air hunted pipe, 44. leading to the i the ratio It should be noted, in this connection, that the average temperature of. the mass of coal or other material. in the retorts, is ll'lllcj.

lower than the temperature of the retorts itcd in themselves. Any increase in the heat passinginto the retort goes to hasten the process of distillatirm, or carbonization as it 1S usually termed, and not, to any great extent,-

to raising the temperature of the coal. This is true as long as the coal is uncarbonized; and, since ii the aim to remove from the retorts the sidual coke as soon as most of the yolaailrmatter of the coal has been driven oil, the abore statement is, substantially, true'in the practical operation of gas benches.

It follows, from the above, that any increase one can make in the temperature or the combustion chamber, will, correspondingly, increase the capacity of the hence. Since, in my present in xention, the heat that is used in the preheating of the air and prodo cer is recuporated from the sensible of the waste flue gases, the increased P'on of heat that I 'et in my retort is clear gain. I am, simply, taking i I. from the, otherwise, wasted heat of the 'ases and adding it to the heat utilized, using the producer gas and the air for combustion as the medium of transference. By my invention, I am, therefore, able to carhonize a considc lily greater weis ht of coal. for the same expenditure of fuel. 1n theproducer.

As stated above this invention is not limits rtion to the particular type bench irn'ch hare shown as the presubject 01 s e plication.

. method or operating the gasproducer of the combined producer and gas-tiredfurnace in his case a gas henchwith my present in volition applied ther to, is not, cssontially. dil ferent from that described in my Letters Patent l lo. 829105, dated Aug.

,Llsh, 1900s: the application. of the inrelation is to the type of combined gas pro-- duccr and l rnace LllQl'QlI). described. The

principal dili'erencc is that the hue gases eavingthe retort oven are first passed through rccuiierrtors for heating the producer "as. They their pass into the recuperators -for heating secondary air. During their. naoseqo; through the producer gas m a lower temperature in rocupcrators the flue gases, of course, fall in temperature by an amount corresponding to the quantity of heat which they give up to the producer gas. They, therefore, do not enter the air recuperators at so high a temperature as in the type of bench described in my Letters Patent No. 829105 dated 3mg. 21st, 1906. In this present type of bench, therefore, in order to secure the same iflegree of preheating of the air, I cause the air current, instead of flowing in a direct vertical direction through the recuperators, to flow back and forth in the recuperator in a direction contrary to the direction of flow of the flue gases passing through the smaller l'lues located within the air lilies. Likewise, as described and claimed in the same application, I make the lower fines of the recuperator of metal of a relatively high heat conductivity. In thus causing the air to traverse a comparatively long path through a line of relatively small cross-section, I gain au'important increase in-the elliciency of heat transference from the flue gases to the air. The transmission of heat from one fluid to another through a separating diaphragm depends, not only on the dilference in the temperature between the two fluids, and the time during which they are in contact with the-hat-transmittin f diaphragm, but, also, upon What is of equal importance, the velocities of the two fluids along the surfaces of the transmitting dia 'vhragnis. The quantity of heat talu-n, unirom or given out to aheat-transmitting surface by a fluid is proportional to the square root or": the velocity of lio v or the fluid along the surface. This factor is of even greater importance when the heattransmittiing diaphragm isas in part if the reeuperator We are now consideriug o a rough porous surface. The combination of this type of rccuperator with. the rccunerator for heating the producer is, therefore, a point of great importance, and it is in this combination Which. gives my invention, as a Whole, great practical utility.

This invention is particularly :pplicable to producers in which bituminous coal, ligoite, or any other fuel containing a. large amount of volatile matter is used in the produccr. In this Ease, the rapid evolutionof volatile matter immediately a flier charging greatly reduces the temperature of the gas leading the producer. This, in turn, results the retort oven, or furnace, and in consequhnce subjects the retorts with their contents to a decided chilling ciicct, By my invention this irregularity of operation is entirely avoided.

Having described my invention, what claim is:-

1. In conihina n, a gas-tired flu-trace, a heat recuperator ior heating combustible gas eupplie to said furnace, a heat recupcrator Ell"! and. a passage [.JJLS f the "cwn gas-heating i-eiglu'mbend flue uses; and a flue ting gases for stible gas, said ail heating rising a lGill'ilIl-bfllld flue eating gases and a return ting gase", the hentinggas Hum-s, whereby the 1g 1:, ing s fine for ting air, the said ail.

cting he: c to $11161 Q-Ul for conduc supn tor south coin! m era iecupei'ator bciny upei 111C cugmrator v2 cwnductlng 11 13:16 then though C gilri i025 for a for p m4 new 5 i'svcuperzi lull, :1 furnace r u: s mic a human,

:cccup arator throng 5.115; c031 heating sax conducted first recuperate and u'ting IGCUPP: miatlon, a gas-producing furectin :1 acupmi'n tors d 0216 mi said IGCUPQ} V located. on one side of mi i 100 heat surname, two reting combustible gas proi furnace, one of g recuperseated on each side of 2mg imnaca, and vertical ndncting hot; v the burning 0 (1 a fine in burning saicL combzucl mr-heatln icii heating recupcrators 0d b'v i'ocfh spending gasJieziting re 1 form bio gm cu ps -n,

i'fiistible gm.

mints likewise i @111 1 said benmth the cupei'utoi said 0 for :1 11d. two 1:

genera 1.66 101' burn- 0n one :rimpos.

a flu-n:

W0 rscuperu ombustibie air for supporting m ion of 811K}. combustibie gas, one 11g and. said nir- 111g located gas hefitatom min in 51! p a furnace in I! asq i;

for heating TBS combur ing heating said Q of eat" P fine said 2 congas

Ting

com

abustibie nSil g'G p 1" 36h cmnbuptlon moat trans- 1 pa inc 0 conducting hot 105 or aofliiuctin 11d a fine unsi- L 1 1 NJ 0 Q, ii: in

com in'ibmg a fine for g s Fm heaiing 50, i cmmraimt recn )(1114 vatmg u cm iucaing the 115 FY04 mince, one

izi'ted 0n each e 01: szm

u'ning said lion gas line for conducting soul combustible.

- gas, saicl air-heating recuperallors likewise each comprising a flue for coiuluciing llUC combustion gases and flue in heat-transferring relationship Willi siiid hot combuslion gas flue for conducting air, a conduit for connecting the combustion gas flue of each gas-heating recuperator -iili the coinbustion gas flue of the corresponding sirliesting recuperator ii plurality ofconduits for conducting combustible gas from said gasproclucing furnace to each of said gasheating recuperators, and a plurality of conduits for co iducting heated air from said air-heating recuperator to said gas: consuming furnace.

10. The structure comprising in conibiniilion, a gas-producing furnace for producing combustible side closures and & lop closure for said gas-producing furnace, gas-consuming furnace located above the top closure of said gas-producing furnace, a reouperotor for heating combustible gas and a I recuperasoi' for heating air located on each side of said gas-producing furnace without "the side closures of the some ssicl airbaseing i'ecuperaiors being located beneath the corresponding gss hesting recuperetors, each of said reouperctors for heating gas comprising- 2), conduit for conducting hot combustion gases from said gas-consuming furnace and o conduit for conducting con:- bustible gas, said conduits being in best transferring rel iiionsl'iip scicl sir-heating recuperzu'zors each comprising c conduit for concluciing combustion gases and. a conduit for conducting air, soi conduits being; in liecotransferring relationship, conduitconnecting the inlei end of the combustion gas conduit of each gas-beating recuperatinwith said gasconsuming furnace, and a conduit connecting the outlet cn'i of the combustion gas conduit of each gas-healing recupcrutor with inlet encl of illQCUlHbliS- tion gas conduit tli= corresponding ciriicziting reouper lirelib? or conciinis l 1 A in econ. o: the '"lc C30 Les oi (.lucing i urnacs cauiduci'ing c use from J I .ower part of she .1 i of the correswmliiig WLS'iICH recuperator, and {L p urzilito l local-toil in be top-cl sure of k 1 oncluc lin ,l (v iousi'iblo ,gus iron {he combustiblegas i fll-Zl gusiicaling recuperuiois lo the combustion chamber of mail 41 pluruliiy -cutcd our lroiu the upper purl of the oonr said oir-lieaiino rcouperz. tion chamber or said guscon 11. The struc'iure coinpi'i tion, a gas-producing furnace prom" combustible gas, Slilfi closures I closure for saicl gcflproclw gas-consuming furnace lO'CL top-closure of said c recuperctor licci' u and a recuperstoifor lieziti each side of said gas-crop" without the side-closure air-heating recuf crctors neath the correspoiuling periiiors, each of said iug gas conrorising a, co not combustion gases i ing furnace and a. comic; combustible gas, said concluicctransferring relationship recuperators each coinpris' conducting combus bi for conduciing sir, i beat-transferring connecting inlet conduit of each I with the said gas-cons conduit connecting ll: combustion gas conduit ing recuperaior with combustion conduii of l ziiulicating recupeiuior, at riuiits in each of ilic said aid gusmroclucing furnace inbustible' gus- Il'iOlii s- 5 eniii gas conriuit of bile corrc ing lElCllP'dl'lliOfl'zlllCl 3 pb loco'tecl in the tr: clucing; furnace bustiblc from l'll" combustible gar heating rccuperuo the chamber of said gas-consuming u plurality of ii'oncluiis for uulucliiiig ccl air from l'llE upper par" of llzc \llili. of such oi s ul uir-iu="ii for said are ' furnace, a gas-consumin furnace, an equalizing flue for air located in each of side-closures, a passage connecting each of said equalizing flue with a source of heated air, a distributing flue for air located above and substantially parallel to each of said equalizing ilues a plurality of da'mpered passages connecting each equalizing line with its cooperating distributing flue a plurality of conduits in each of the side-cl0- sures of said gas-producirg furnace for conducting combustible from said furnace to a gas-heating means, plurality of conduits in the top-closure of said gas-pz'odud ing furnace for conducting lioi, coinbus't-il'fle gas from i gas-heating; means to the combustion chamber of said gas-consumiilg 1' image, a pluralityof conduits coiiiice' a said fi iiiesses (limos. CARTER, ,UOUXS FLHTONSAIWP? 

